Comparison of the overall intelligibility, articulation, resonance, and voice characteristics between children using cochlear implants and those using bilateral hearing aids: a pilot study

Measuring speech intelligibility with deaf and hard-of-hearing children: A systematic review

There is great variability in the ways in which the speech intelligibility of d/Deaf and hard-of-hearing (DHH) children who use spoken language as part, or all, of their communication system is measured. This systematic review examined the measures and methods that have been used when examining the speech intelligibility of children who are DHH and the characteristics of these measures and methods. A systematic database search was conducted of CENTRAL; CINAHL; Cochrane; ERIC; Joanna Briggs; Linguistics, Language and Behavior Abstracts; Medline; Scopus; and Web of Science databases, as well as supplemental searches. A total of 204 included studies reported the use of many different measures/methods which measured segmental aspects of speech, with the most common being Allen et al.'s (2001, The reliability of a rating scale for measuring speech intelligibility following pediatric cochlear implantation. Otology and Neurotology, 22(5), 631-633. https://doi.org/10.1097/00129492-200109000-00012) Speech Intelligibility Rating scale. Many studies included insufficient details to determine the measure that was used. Future research should utilize methods/measures with known psychometric validity, provide clear descriptions of the methods/measures used, and consider using more than one measure to account for limitations inherent in different methods of measuring the speech intelligibility of children who are DHH, and consider and discuss the rationale for the measure/method chosen.

Spontaneous speech intelligibility: early cochlear implanted children versus their normally hearing peers at seven years of age

Speaking intelligibly is an important achievement in children's language development. How far do congenitally severe-to-profound hearing-impaired children who received a cochlear implant (CI) in the first two years of their life advance on the path to intelligibility in comparison to children with typical hearing (NH)? Spontaneous speech samples of children with CI and children with NH were orthographically transcribed by naïve transcribers. The entropy of the transcriptions was computed to analyze their degree of uniformity. The same samples were also rated on a continuous rating scale by another group of adult listeners. The transcriptions of the NH children's speech were more uniform, i.e., had significantly lower entropy, than those of the CI children, suggesting that the latter group displayed lower intelligibility. This was confirmed by the ratings on the continuous scale. Despite the relatively restricted age ranges, older children reached better intelligibility scores in both groups.

The Acquisition of Acoustic Cues to Onset and Coda Voicing Contrasts by Preschoolers With Hearing Loss

PURPOSE

Children with hearing loss (HL), including those with hearing aids (HAs) and cochlear implants (CIs), often have difficulties contrasting words like " b each" versus " p each" and "do g " versus "do ck " due to challenges producing systematic voicing contrasts. Even when acoustic contrasts are present, these may not be perceived as such by others. This can cause miscommunication, leading to poor self-esteem and social isolation. Acoustic evidence is therefore needed to determine if these children have established distinct voicing categories before entering school and if misperceptions are due to a lack of phonological representations or due to a still-maturing implementation system. The findings should help inform more effective early intervention.

METHOD

Participants included 14 children with HL (eight HA users, five CI users, and one bimodal) and 20 with normal hearing, all English-speaking preschoolers. In an elicited imitation task, they produced consonant-vowel-consonant minimal pair words that contrasted voicing in word-initial (onset) or word-final (coda) position at all three places of articulation (PoAs).

RESULTS

Overall, children with HL showed acoustically distinct voicing categories for both onsets and codas at all three PoAs. Contrasts were less systematic for codas than for onsets, as also confirmed by adults' perceptual ratings.

CONCLUSIONS

Preschoolers with HL produce acoustic differences for voiced versus voiceless onsets and codas, indicating distinct phonological representations for both. Nonetheless, codas were less accurately perceived by adult raters, especially when produced by CI users. This suggests a protracted development of the phonetic implementation of codas, where CI users, in particular, may benefit from targeted intervention.

Native and non-native listeners' judgements on the overall speech quality of hearing-impaired children

This study focuses on the influence of listeners' native language on their judgement of the overall speech quality of normally hearing (NH) and hearing-impaired (HI) children. Studies have shown that listeners' native language influences their judgements on linguistic aspects of a foreign language. Since judging speech quality does in principle not require any knowledge of the language, the question arose if the native language influences listeners' judgements. For this purpose, the overall speech quality of seven-year-old Dutch speaking children (n = 21) with an acoustic hearing aid (HA), a cochlear implant (CI) and normal hearing (NH) was judged by four listener groups (native speakers of Italian, German, French and Dutch). Listeners completed a comparative judgement task in which stimuli were presented in pairs. For each pair, they selected the better sounding stimulus. This procedure ultimately led to a ranking of the stimuli according to their speech quality. The ranking showed that NH children had a significantly higher speech quality than HI children. Interestingly, there was no significant effect of language background. Both native and non-native listeners perceived a significant difference in speech quality. Also, within the group of HI children, all listener groups preferred the speech of CI children when comparing them to HA children. These results indicated that the differences were purely speech related since the non-native listeners had no linguistic knowledge of Dutch. Considering that all listeners perceived a similar qualitative difference, we conclude that there was no transfer of native language in this type of judgement.

Predicting speech-sound disorder outcomes in school-age children with hearing loss: The VicCHILD experience

BACKGROUND

Congenital hearing loss is the most common birth anomaly, typically influencing speech and language development, with potential for later academic, social and employment impacts. Yet, surprisingly, the nuances of how speech is affected have not been well examined with regards to the subtypes of speech-sound disorder (SSD). Nor have the predictors of speech outcome been investigated within a sizeable population cohort.

AIMS

(1) To describe the subtypes and prevalence of SSD in children with hearing loss. (2) To determine which characteristics of hearing loss predict the presence of SSD.

METHODS & PROCEDURES

A total of 90 children (5-12 years of age) with permanent hearing loss were recruited from an Australian population cohort. Children completed a standardized speech assessment to determine the presence and subtype of SSD. Logistic regression was used to determine the predictors of speech outcome. Demographic, developmental and hearing-related predictors were examined.

OUTCOMES & RESULTS

The prevalence of speech disorder overall was 58%, with the most common subtype being phonological delay in 49% of the sample. Factors most predictive of speech disorder were being male, younger and a bimodal user (i.e., using both a hearing aid and a cochlear implant).

CONCLUSIONS & IMPLICATIONS

This is the first study, in a sizeable cohort, to describe the prevalence and predictive factors for SSD associated with hearing loss. Clinically, it could be beneficial to implement earlier targeted phonological interventions for children with hearing loss. What this paper adds What is already known on this subject Speech issues are common in children with hearing loss; however, the breakdown of subtypes of SSD (e.g., articulation versus phonological disorder) have not been previously described in a population cohort. This distinction is relevant, as each subtype calls for specific targeted intervention. Studies examining factors predictive of speech outcomes, across a range of hearing levels, are also lacking in a population cohort. What this paper adds to existing knowledge Data suggest the most common type of SSD in children with hearing loss is phonological delay. Males, younger children, and bimodal users were at greater risk of having a subtype of SSD. What are the potential or actual clinical implications of this work? The results are clinically pertinent as the speech diagnosis determines the targeted treatment. Phonological delay is responsive to treatment, and early targeted intervention may improve prognosis for speech outcomes for children with hearing loss.

Development of fricative production in French-speaking school-aged children using cochlear implants and children with normal hearing

In the course of productive phonological development, fricatives are among the last speech sounds to emerge and to be mastered by children, probably because of the high degree of articulatory precision they require or because of difficulties with their perception. Children with cochlear implants (CI) face additional difficulties with fricative perception, since high spectral frequency components are shown to be especially difficult to perceive with a cochlear implant. Studying fricative production in children with CIs allows to study how the partial transmission of speech sounds by cochlear implants influences children's speech production, and therefore to explore how perceptual abilities influence the late stages of phonological development. This acoustic study focuses on fricative production at three places of articulation (i.e., /f/, /s/ and /ʃ/), comparing productions by two groups of children (20 children with normal hearing (NH) vs. 13 children with CIs, all aged 5;7 to 10;7 years), and taking into account their consistency in coarticulation and the stability of their production across two different tasks (word-repetition and picture-naming). Statistical analyses were carried out by means of linear mixed-effect models. The results show that while both groups produce /ʃ/ with similar acoustic characteristics, between-group differences are found for /f/ and /s/. Furthermore, effects of consonant-vowel coarticulation are found for children with NH, and are absent for children with CIs. Effects of chronological age are only found for children with CIs (production in older children with CIs nearing that of children with NH). Our study shows that the development of fricative production of five- to 11-year-old children with CIs is affected by the children's hearing abilities and late access to auditory information. These limitations however do not prevent the children from eventually reaching a consistency similar to that of children with NH, as suggested by the fact that their production is still evolving during that age span. The results also show that the acquisition of coarticulation strategies can be impeded by degraded or delayed access to audio.

Long-term effects of cochlear implantation on the intelligibility of speech in French-speaking children

Our study compares the intelligibility of French-speaking children with a cochlear implant (N = 13) and age-matched children with typical hearing (N = 13) in a narrative task. This contrasts with previous studies in which speech intelligibility of children with cochlear implants is most often tested using repetition or reading tasks. Languages other than English are seldom considered. Their productions were graded by naive and expert listeners. The results show that (1) children with CIs have lower intelligibility, (2) early implantation is a predictor of good intelligibility, and (3) late implantation after two years of age does not prevent the children from eventually reaching good intelligibility.

Rating the overall speech quality of hearing-impaired children by means of comparative judgements

OBJECTIVE

Acoustic measurements have shown that the speech of hearing-impaired (HI) children deviates from the speech of normally hearing (NH) peers. The aim of the present study is to examine whether listeners with varying degrees of experience with (HI) children's speech perceive a difference in the overall speech quality of seven-year-old NH children and their HI peers who received a device before the age of two.

METHOD

Short speech samples of seven children with NH, seven children with an acoustic hearing aid (HA) and seven children with a cochlear implant (CI) were judged by three groups of listeners (audiologists, primary school teachers and inexperienced listeners) in a comparative judgement task. In this task, listeners compared stimuli in pairs and decided which stimulus sounded better, leading to a ranking of the stimuli according to their overall speech quality.

RESULTS

The ranking showed that the overall speech quality differed considerably for HI and NH children. The latter group had a significantly higher overall speech quality than HI children. In the group of HI children, children with CI were ranked higher than children with HA. Moreover, length of device use was found to have a significant effect in the group of children with CI: longer device experience led to better ratings. This effect was significantly less strong in HA children. No significant differences were found between the three groups of listeners.

CONCLUSION

Listeners agree that the speech of NH children sounds better than the speech of HI children. This result indicates that even after almost seven years of device use, the speech of HI children still differs from the speech of NH children. The overall speech quality of CI children was better than that of HA children, and this effect increased with longer device use. No effect of listeners' experience with (NH and/or HI) children's speech was established.

Voz de crianças e adolescentes deficientes auditivos e pares ouvintes: influência da percepção auditiva da fala na produção vocal

RESUMO Objetivo: Comparar os resultados acústicos e perceptivo-auditivos da voz de crianças e adolescentes deficientes auditivos com pares ouvintes e correlacionar estes resultados com o relato dos pais em relação à percepção auditiva da fala. Método: Os participantes foram divididos em dois grupos: grupo I, 20 crianças e adolescentes deficientes auditivos, e grupo II, 20 crianças e adolescentes ouvintes. Foi realizada análise acústica da vogal /a/ e avaliação perceptivo-uditiva da vogal /a/ e da fala. A percepção auditiva do GI foi avaliada utilizando a Escala de Integração Auditiva Significativa para Crianças Pequenas e a Escala de Integração Auditiva Significativa, com adaptação para participantes adolescentes. Os resultados acústicos e perceptivo-auditivos da voz de GI e GII foram comparados e, para o GI, estes resultados foram correlacionados com o desempenho na percepção auditiva. Resultados: Os grupos I e II apresentaram resultados similares, diferenciando-se estatisticamente nos parâmetros variação da frequência fundamental (vF0) e variação da amplitude (vAm) da vogal /a/ e ressonância da fala. Houve correlação negativa entre o desempenho na percepção auditiva com os parâmetros de jitter, vF0 e grau geral da vogal /a/. Conclusão: A qualidade vocal do GI foi semelhante em praticamente todos os parâmetros vocais analisados a dos seus pares ouvintes (G2). A percepção auditiva influenciou os parâmetros jitter, vF0 e grau geral do impacto da voz, em que crianças e adolescentes deficientes auditivos que apresentaram maiores escores para a percepção auditiva também foram capazes de manter a emissão vocal mais equilibrada.

Voice Quality in Cochlear Implant Recipients: An Observational Cross Sectional Study

Children with hearing loss are more likely to suffer from voice and speech disorders than with normal hearing due to their poor and less robust auditory feedback mechanisms. Prelingually deaf children are not able to supervise their own voice due to lack of auditory feedback. Cochlear implanted children achieve better hearing and consequently enhanced speech intelligibility. Various parameters of voice improve with continous usage of cochlear implant. However all the vocal parameters do not show similar degree of change. Previous studies have assessed the voice quality of cochlear implantees and have given inconsistent results. The aim of the study is to compare the voice quality of cochlear implant children with normal subjects using objective and subjective methods. The study was undertaken after obtaining clearance from the Institutional Ethics committee. Written informed consent for carrying out voice analysis was taken from the parents. The voice analysis of 42 normal and 42 cochlear implant children were done using the Dr Voice software by Tiger Inc. All the children were age and sex matched. The parameters assessed were fundamental frequency, maximum phonation time, jitter%, shimmer% and harmonics to noise ratio. The findings of both the group were compared. The cochlear implanted children showed significant deviation of all the measured parameters as compared to the normal children. The voice quality of the implanted children is poor and deviant from the normal. Even after continuous usage of cochlear implant for 1 year the voice quality of these children did not reach to the levels of their normal hearing peers.

Prosody perception and production by children with cochlear implants

The perception and production of emotional and linguistic (focus) prosody were compared in children with cochlear implants (CI) and normally hearing (NH) peers. Thirteen CI and thirteen hearing-age-matched school-aged NH children were tested, as baseline, on non-verbal emotion understanding, non-word repetition, and stimulus identification and naming. Main tests were verbal emotion discrimination, verbal focus position discrimination, acted emotion production, and focus production. Productions were evaluated by NH adult Dutch listeners. All scores between groups were comparable, except a lower score for the CI group for non-word repetition. Emotional prosody perception and production scores correlated weakly for CI children but were uncorrelated for NH children. In general, hearing age weakly predicted emotion production but not perception. Non-verbal emotional (but not linguistic) understanding predicted CI children's (but not controls') emotion perception and production. In conclusion, increasing time in sound might facilitate vocal emotional expression, possibly requiring independently maturing emotion perception skills.

Basic Measures of Prosody in Spontaneous Speech of Children With Early and Late Cochlear Implantation

PURPOSE

Relative to normally hearing (NH) peers, the speech of children with cochlear implants (CIs) has been found to have deviations such as a high fundamental frequency, elevated jitter and shimmer, and inadequate intonation. However, two important dimensions of prosody (temporal and spectral) have not been systematically investigated. Given that, in general, the resolution in CI hearing is best for the temporal dimension and worst for the spectral dimension, we expected this hierarchy to be reflected in the amount of CI speech's deviation from NH speech. Deviations, however, were expected to diminish with increasing device experience.

METHOD

Of 9 Dutch early- and late-implanted (division at 2 years of age) children and 12 hearing age-matched NH controls, spontaneous speech was recorded at 18, 24, and 30 months after implantation (CI) or birth (NH). Six spectral and temporal outcome measures were compared between groups, sessions, and genders.

RESULTS

On most measures, interactions of Group and/or Gender with Session were significant. For CI recipients as compared with controls, performance on temporal measures was not in general more deviant than spectral measures, although differences were found for individual measures. The late-implanted group had a tendency to be closer to the NH group than the early-implanted group. Groups converged over time.

CONCLUSIONS

Results did not support the phonetic dimension hierarchy hypothesis, suggesting that the appropriateness of the production of basic prosodic measures does not depend on auditory resolution. Rather, it seems to depend on the amount of control necessary for speech production.

Vocal Biomarkers of Mild-to-Moderate Hearing Loss in Children and Adults: Voiceless Sibilants

PURPOSE

The purpose of this study was to determine if an objective measure of speech production could serve as a vocal biomarker for the effects of high-frequency hearing loss on speech perception. It was hypothesized that production of voiceless sibilants is governed sufficiently by auditory feedback that high-frequency hearing loss results in subtle but significant shifts in the spectral characteristics of these sibilants.

METHOD

Sibilant production was examined in individuals with mild to moderately severe congenital (22 children; 8-17 years old) and acquired (23 adults; 55-80 years old) hearing losses. Measures of hearing level (pure-tone average thresholds at 4 and 8 kHz), speech perception (detection of nonsense words within sentences), and speech production (spectral center of gravity [COG] for /s/ and /ʃ/) were obtained in unaided and aided conditions.

RESULTS

For both children and adults, detection of nonsense words increased significantly as hearing thresholds improved. Spectral COG for /ʃ/ was unaffected by hearing loss in both listening conditions, whereas the spectral COG for /s/ significantly decreased as high-frequency hearing loss increased. The distance in spectral COG between /s/ and /ʃ/ decreased significantly with increasing hearing level. COG distance significantly predicted nonsense-word detection in children but not in adults.

CONCLUSIONS

At least one aspect of speech production (voiceless sibilants) is measurably affected by high-frequency hearing loss and is related to speech perception in children. Speech production did not predict speech perception in adults, suggesting a more complex relationship between auditory feedback and feedforward mechanisms with age. Even so, these results suggest that this vocal biomarker may be useful for identifying the presence of high-frequency hearing loss in adults and children and for predicting the impact of hearing loss in children.

Can listeners hear the difference between children with normal hearing and children with a hearing impairment?

Acoustic measurements have shown that the speech of hearing-impaired (HI) children differs from that of normally hearing (NH) children, even after several years of device use. This study focuses on the perception of HI speech in comparison to NH children's speech. The purpose of this study was to investigate whether adult listeners can identify the speech of NH and HI children. Moreover, it is studied whether listeners' experience and the children's length of device use play a role in that assessment. For this study, short utterances of 7 children with a cochlear implant (CI), 7 children with an acoustic hearing aid (HA) and 7 children with NH were presented to 90 listeners who were required to specify the hearing status of each speech sample. The judges had different degrees of familiarity with hearing disorders: there were 30 audiologists, 30 primary schoolteachers and 30 inexperienced listeners. The results show that the speech of children with NH and HI can reliably be identified. However, listeners do not manage to distinguish between children with CI and HA. Children with CI are increasingly identified as NH with increasing length of device use. For children with HA, there is no similar change with longer device use. Also, experienced listeners seem to display a more lenient attitude towards atypical speech, whereas inexperienced listeners are stricter and generally consider more utterances to be produced by children with HI.

Phonological processes in the speech of school-age children with hearing loss: Comparisons with children with normal hearing

PURPOSE

In this descriptive study, phonological processes were examined in the speech of children aged 5;0-7;6 (years; months) with mild to profound hearing loss using hearing aids (HAs) and cochlear implants (CIs), in comparison to their peers. A second aim was to compare phonological processes of HA and CI users.

METHOD

Children with hearing loss (CWHL, N = 25) were compared to children with normal hearing (CWNH, N = 30) with similar age, gender, linguistic, and socioeconomic backgrounds. Speech samples obtained from a list of 88 words, derived from three standardized speech tests, were analyzed using the CASALA (Computer Aided Speech and Language Analysis) program to evaluate participants' phonological systems, based on lax (a process appeared at least twice in the speech of at least two children) and strict (a process appeared at least five times in the speech of at least two children) counting criteria.

RESULTS

Developmental phonological processes were eliminated in the speech of younger and older CWNH while eleven developmental phonological processes persisted in the speech of both age groups of CWHL. CWHL showed a similar trend of age of elimination to CWNH, but at a slower rate. Children with HAs and CIs produced similar phonological processes. Final consonant deletion, weak syllable deletion, backing, and glottal replacement were present in the speech of HA users, affecting their overall speech intelligibility.

CONCLUSIONS

Developmental and non-developmental phonological processes persist in the speech of children with mild to profound hearing loss compared to their peers with typical hearing. The findings indicate that it is important for clinicians to consider phonological assessment in pre-school CWHL and the use of evidence-based speech therapy in order to reduce non-developmental and non-age-appropriate developmental processes, thereby enhancing their speech intelligibility.

Cultural Identity of Young Deaf Adults with Cochlear Implants in Comparison to Deaf without Cochlear Implants and Hard-of-Hearing Young Adults

This study examined the relationships between cultural identity, severity of hearing loss (HL), and the use of a cochlear implant (CI). One hundred and forty-one adolescents and young adults divided into three groups (deaf with CI, deaf without CI, and hard-of-hearing (HH)) and 134 parents participated. Adolescents and young adults completed questionnaires on cultural identity (hearing, Deaf, marginal, bicultural-hearing, and bicultural-deaf) and communication proficiencies (hearing, spoken language, and sign language). Parents completed a speech quality questionnaire. Deaf participants without CI and those with CI differed in all identities except marginal identity. CI users and HH participants had similar identities except for a stronger bicultural-deaf identity among CI users. Three clusters of participants evolved: participants with a dominant bicultural-deaf identity, participants with a dominant bicultural-hearing identity and participants without a formed cultural identity. Adolescents and young adults who were proficient in one of the modes of communication developed well-established bicultural identities. Adolescents and young adults who were not proficient in one of the modes of communication did not develop a distinguished cultural identity. These results suggest that communication proficiencies are crucial for developing defined identities.

The Acoustic Characteristics of the Voice in Cochlear-Implanted Children: A Longitudinal Study

OBJECTIVE

The purpose of this study was to characterize changes in the voice and vowel articulation of prelingually deaf children after cochlear implantation.

METHODS

In this study, the patient group included 30 prelingually deaf children who underwent unilateral cochlear implantation at 4-6 years of age. The control group included normally hearing children of the same age. All deaf children had follow-ups before cochlear implantation and at 1, 3, 6, 12, and 24 months after implantation. The acoustic parameters, aerodynamic parameters, and vowel formants were measured in the patient group and compared with those of the control group.

RESULTS

All acoustic parameters, aerodynamic parameters, and vowel formants differed significantly between normally hearing children and prelingually deaf children. For prelingually deaf children, all of the above parameters gradually decreased after cochlear implantation. Furthermore, the acoustic parameters Jitter and Shimmer were significantly reduced as early as 6 months, whereas the fundamental frequency, the standard deviation of fundamental frequency, estimated subglottal pressure, aF1, iF2, and uF2 were significantly altered 12 months after implantation. However, statistically significant differences in these parameters were not observed between 12 and 24 months after cochlear implantation.

CONCLUSION

After cochlear implantation, prelingually deaf children established auditory feedback and improved voice control and vowel production.

Objective Voice Analysis of Pediatric Cochlear Implant Recipients and Comparison With Hearing Aids Users and Hearing Controls

OBJECTIVES

Phonation is influenced by hearing as a feedback mechanism. The purpose of the present study was to compare selected acoustic parameters in children using cochlear implants (CIs), those using hearing aids (HA), and their normal-hearing (NH) peers.

METHODS

The participants were 15 children using CI (mean age: 72 months), 15 children using HA (mean age: 74 months), and 15 NH children (mean age: 77 months). The vowel /a/ was produced to measure perturbation and mean fundamental frequency. The six Persian vowels in /C_bVC_d/ were obtained to extract vowel duration. Data were analyzed by one-way analysis of variance.

RESULTS

Results revealed a statistically significant difference between the NH group and the HA group regarding fundamental frequency (F_2,51 = 3.443, P < 0.05), jitter local (F_2,51 = 1.629, P < 0.05), jitter local absolute (F_2,51 = 6.519, P < 0.001), jitter rap (F_2,51 = 7.151, P < 0.001), jitter ppq5 (F_2,51 = 5.894, P < 0.001), shimmer local (%) (F_2,51 = 8.070, P < 0.001), shimmer local (dB) (F_2,51 = 3.884, P < 0.05), shimmer apq3 (F_2,51 = 4.926, P < 0.05), shimmer apq5 (F_2,51 = 8.442, P < 0.001), and harmonic-to-noise ratio (F_2,51 = 4.117, P < 0.001). The mean values of the duration of all six vowels were significantly greater in children with CI and HA than in NH children (P < 0.001).

CONCLUSION

It seems that after 8 months of using CI, auditory control of voice production would be enabled. Furthermore, children with hearing impairment potentially regard vowel sound duration as a distinguishing feature, whereas in NH speakers, the duration has the least effect in vowel identification.

Word initial fricative production in children with cochlear implants and their normally hearing peers matched on lexicon size

Fricative production is affected in children with cochlear implants (CI) as compared to age-matched normally hearing (NH) children. However, the phonological development of children with CI is rarely compared to that of NH peers matched on lexicon size. We compare the early word initial fricative development of 10 children with CI and 30 NH children matched on lexicon size and on chronological age. Children with CI are expected to differ from their NH peers when they are matched on chronological age. But, are lexical development and phonological development commensurate in children with CI as they have been shown to be in NH children? Results show that fricative production in children with CI deviates from that of age-matched NH peers. The differences between both groups disappear when they were matched on lexicon size. Thus, phonological development in children with CI is similar to that of their NH peers with comparable lexicon sizes.

Consonant discrimination by Mandarin-speaking children with prelingual hearing impairment

OBJECTIVES

Little is known about the consonant discrimination ability of Mandarin-speaking children with prelingual hearing impairment (HI) and fitted with hearing aids (HAs). The present study aimed to evaluate Mandarin consonant discrimination ability in children with HI, and explore the effects of unaided and aided hearing threshold, the age of first HA fitting and the duration of HA use on consonant discrimination ability.

METHODS

Subjects were Mandarin-speaking children aged 5;4-12;6 years with profound HI (n=41), children aged 6;1-12;4 years with severe HI (n=26), and children aged 5;0-11;9 years with moderate HI (n=9). The Mandarin Consonant Discrimination Test was administered in six test conditions: -10, -5, 0, 5 and 10dB signal to noise ratios (S/Ns) and quiet. HAs were in the usual user's settings, adjusted to match the manufacturer prescribed settings and individual preferences, and the volume was set to comfortable listening level.

RESULTS

The results revealed that /p(h)/-/t(h)/, /ts/-/tʂ/ and /ʐ/-/l/ were the most difficult and /p/-/p(h)/, /t/-/t(h)/, /tɕ/-/tɕ(h)/ and /k/-/k(h)/ were the easiest consonant minimal pairs to discriminate in quiet both for children with profound HI and those with moderate to severe HI. In noise, no significant difference in performance was found among all consonant minimal pairs. A backward elimination stepwise multiple linear regressions revealed that unaided hearing level accounted for 25.4% of the variance in consonant discrimination performance in noise at 10dB S/N and 30.4% in quiet. However, aided hearing threshold, the age of first HA fitting and the duration of HA use did not significantly predict consonant discrimination ability both in quiet and in noise.

CONCLUSIONS

Consonant discrimination performance of children with profound HI was poorer than those with moderate to severe HI. The ability to discriminate consonant pairs seems to depend on age of acquisition of the consonants. Although the age of first HA fitting and the duration of HA use were not correlated with consonant discrimination outcomes, this finding does not preclude the importance of early HA fitting.

Nasalance and nasality in children with cochlear implants and children with hearing aids

OBJECTIVES

In prelingually deaf children, many speech production aspects including resonance, are known to be problematic. This study aimed to investigate nasality and nasalance in two groups of prelingually hearing impaired children, namely deaf children with a cochlear implant (CI) and moderate-to-severely hearing impaired hearing aid (HA) users. The results of both groups are compared with the results of normal hearing children. Besides, the impact of the degree of hearing loss was determined.

METHODOLOGY

36 CI children (mean age: 9;0y), 25 HA children (mean age: 9;1y) and 26 NH children (mean age: 9;3y) were assessed using objective assessment techniques and perceptual evaluations in order to investigate the nasal resonance of the three groups. Ten HA children had thresholds above 70dB (range: 91dB-105dB) and fifteen below 70dB (range: 58dB-68dB). The Nasometer was used for registration of the nasalance values and nasality was perceptually evaluated by two experienced speech therapists using a nominal rating scale (consensus evaluation).

RESULTS

For nasal stimuli, both CI children and HA children showed lower nasalance values in comparison with NH children. The opposite was observed for the oral stimuli. In both hearing impaired groups, cul-de-sac-resonance was observed on a significantly larger scale than in the NH group, and the HA children were judged to be significantly more hypernasal in comparison with NH children.

CONCLUSIONS

Despite the fact that a substantial number of the CI and HA children demonstrate normal (nasal) resonance quality, this aspect of speech production is still at risk for hearing impaired children.

Proximate factors associated with speech intelligibility in children with cochlear implants: A preliminary study

The purpose of this descriptive pilot study was to examine possible relationships among speech intelligibility and structural characteristics of speech in children who use cochlear implants. The Beginners Intelligibility Test (BIT) was administered to 10 children with cochlear implants, and the intelligibility of the words in the sentences was judged by panels of naïve adult listeners. Additionally, several qualitative and quantitative measures of word omission, segment correctness, duration, and intonation variability were applied to the sentences used to assess intelligibility. Correlational analyses were conducted to determine if BIT scores and the other speech parameters were related. There was a significant correlation between BIT score and percent words omitted, but no other variables correlated significantly with BIT score. The correlation between intelligibility and word omission may be task-specific as well as reflective of memory limitations.

Systematic analysis of the benefits of cochlear implants on voice production

PURPOSE

To perform a systematic analysis of the research regarding vocal characteristics of hearing impaired children or adults with cochlear implants.

RESEARCH STRATEGY

A literature search was conducted in the databases Web of Science, Bireme, and Universidade de São Paulo's and CAPES' thesis and dissertations databases using the keywords voice, voice quality, and cochlear implantation, and their respective correspondents in Brazilian Portuguese.

SELECTION CRITERIA

The selection criteria included: title consistent with the purpose of this review; participants necessarily being children or adults with severe to profound pre-lingual or post-lingual hearing loss using cochlear implants; and data regarding participants' performance on perception and/or acoustic analysis of the voice.

RESULTS

Twenty seven papers were classified according to the levels of evidence and quality indicators recommended by the American Speech-Language-Hearing Association (ASHA). The designs of the studies were considered of low and medium levels of evidence. Six papers were classified as IIb, 20 as III, and one as IV.

CONCLUSION

The voice of hearing impaired children and adults with cochlear implants has been little studied. There is not an effective number of studies with high evidence levels which precisely show the effects of the cochlear implantation on the quality of voice of these individuals.

Characteristics of nasal resonance and perceptual rating in prelingual hearing impaired adults

Objectives

Resonance problems in hearing impaired (HI) individuals have been described as aspects of nasality. However, there are limitations in being able to explain the range of resonance problems. Therefore, this study suggests a perceptual rating that will effectively explain the characteristics of resonance problems in HI individuals.

Methods

Nasalance scores were obtained from 32 subjects in each of HI and normal hearing (NH) groups using a nasometer. The subjects were categorized into groups based on normal and abnormal nasalance ranges. The abnormal nasalance range group was further divided into hyper-, hypo-, and mixed-nasal groups. Nasalance scores were based the individuals performance in a series of passage and syllable tasks. The perceptual rating was evaluated using a newly introduced tool, 'vertical focus of resonance' (VFR), which focuses on the resonance energy in the frontal, throat, pharyngeal and nasal locations.

Results

The NH group demonstrated a significantly lower nasalance score in the oral coupling and passage tasks than the HI group. Based on the results of nasalance correlation analysis, the HI group showed highly significant correlations between syllable and passage tasks, as contrasted with the NH group. There were significant differences in VFR between the nasalance types in both the NH and the HI groups.

Conclusion

The HI hyper-nasal group showed tendencies of velopharyngeal opening, as opposed to the HI hypo-nasal group which showed tendencies of velopharyngeal closure. The HI mixed-nasal group showed inappropriate coordination of velopharyngeal function. In the HI group, the results of VFR showed that the air flow and the resonance energy were not released from the cavity of resonance. The suggested VFR tool explains the focusing characteristics of resonance energy within a continuation of speech sound regardless of the phonetic environment. Therefore, VFR may be a useful tool in explaining the deviant resonance patterns of HI individuals.

Intelligibility of hearing impaired children as judged by their parents: A comparison between children using cochlear implants and children using hearing aids

OBJECTIVES

The aim of this study was to determine the intelligibility of prelingually deaf children with cochlear implants (CI) as judged by their own parents, and to compare these results with prelingually hearing impaired children using hearing aids (HA) and normally hearing (NH) children. The authors hypothesised that subjects using conventional hearing aids would have poorer intelligibility judgements compared to NH and CI children.

METHODOLOGY

This is a comparative study of 24 prelingually deaf CI children (m.a. 8.3 years), 24 prelingually hearing impaired HA children (m.a. 9.0 years) and 25 NH children. Recorded speech samples at word-, sentence- and story-level were perceptually judged by two speech pathologists and the child's main caregiver (the mother in most cases) using a five-point hierarchical scale. In addition, the sample of each child was transcribed by the child's main caregiver. The investigators counted and determined a percentage of words correctly understood.

RESULTS

The judgements of the speech pathologists and the transcriptions of the mothers were not different between the CI and NH children, although the mothers tended to judge their CI child to be less intelligible. The HA children on the other hand, showed a mean intelligibility inferior to NH and CI children, as demonstrated by the judgements of the mothers and speech pathologists as well as by the percentages of correctly identified words by the mothers.

CONCLUSION

The intelligibility of the prelingually deaf CI children is very close to the intelligibility of NH children, while the HA children still show a decreased mean intelligibility.

The influence of the auditory prosthesis type on deaf children's voice quality

OBJECTIVE

In the last years, technology has made it possible for deaf people, and especially for deaf children, to enter the world of sound and, as a consequence, to facilitate communicative competence in oral language, which used to be an insurmountable obstacle. With this article we are trying to carry out a revision of the descriptions that have traditionally featured deaf children's voice.

METHODS

We analyse the voice quality obtained out of a research with 62 children (35 girls and 27 boys) with profound deafness of several degrees, aged on average 7 years 4 months, and users of different types of auditory prostheses (analogue/digital hearing aids or cochlear implants) experimental group--Voice quality was evaluated from the production of a sustained vowel /a:/ for four-five seconds, considering F(0), jitter, shimmer and NHR values.

RESULTS

The results are compared with the ones obtained from a control group of hearing children (n=54). The Experimental Group shows altered voice quality parameters. Particularly in F(0) (294.079 Hz) and shimmer (0.568 dB), there are statistically significant values in comparison with the control group (p<0.001). With regards to jitter (1.474%), differences were smaller. Nevertheless, the results show how the profiles reached by deaf children are nowadays more similar to those reached by the hearing control group. However, the degree of hearing impairment and the type of prosthesis used can determine the parameters of deaf children's voice quality to a great extent. Thus, the digital hearing aid users are the ones who present better voice quality values: F(0) (265.50 z); jitter (1.009%) and shimmer (0.486 dB); whereas implant users: F(0) (287.93 z); jitter (1.344%) and shimmer (0.526 dB), and particularly analogue hearing aid users: F(0) (323.80 z); jitter (1.999%) and shimmer (0.687 dB), did show significant differences in comparison with the control group of hearing children.

CONCLUSIONS

In the study of voice quality in children with profound hearing loss, it is very important to have information both about the degree of hearing loss and the kind of prosthesis used. Implant users show more altered voice quality than digital hearing aid users. However, the hearing loss they compensate is much more important than the hearing loss compensated by the hearing aids. Therefore, we consider that both prostheses help children with hearing loss to have a more normalized voice quality than what scientific literature has traditionally stated. Finally, we question the validity of using some acoustic parameters as indicators of voice quality in deaf children having no laryngeal problems.

A comparison of the consonant production between Dutch children using cochlear implants and children using hearing aids

OBJECTIVES

The main purpose of the present study was to compare the consonant error patterns of Dutch prelingually deaf CI children with prelingually hearing-impaired hearing aid (HA) children. The authors hypothesized that subjects using conventional hearing aids would have poorer consonant production skills. Additionally, the impact of the age at implantation (CI) and the degree of hearing loss (HA) was determined.

METHODOLOGY

This is a comparative study of 29 prelingually deaf CI children (m.a. 9;0 y) and 32 prelingually hearing-impaired HA children (m.a. 9;11 y) who received their first hearing aid before the age of 2 years. Nineteen CI children were implanted before the age of 5 years. Nine HA children had thresholds above 90dB (range: 91-105dB), 15 between 70 and 90dB (range: 72-90dB) and 8 below 70dB (range: 58-68dB). Speech samples of all the children were elicited by means of a picture naming test and were video-recorded for further phonetic and phonological analysis.

RESULTS

Considerably more phonetic and phonologic errors were observed in the HA children with thresholds above 70dB (range: 72-105dB). No notable differences could be found between deaf CI children and HA children with thresholds below 70dB. Even children implanted after the age of 5 years showed significantly fewer phonetic and phonological errors than HA children.

CONCLUSION

The consonant production of implanted children is more adequate than the consonant production of HA children with a hearing loss of 70dB or more. In addition, the results also indicate that even after the age of 5 years, implantation can still have an advantageous effect on a child's consonant production.

Executive function and language in deaf children

The relationship between language and executive function (EF) and their development in children have been the focus of recent debate and are of theoretical and clinical importance. Exploration of these functions in children with a peripheral hearing loss has the potential to be informative from both perspectives. This study compared the EF and language skills of 8- to 12-year-old children with cochlear implants (n = 22) and nonimplanted deaf children (n = 25) with those of age-matched hearing controls (n = 22). Implanted and nonimplanted deaf children performed below the level of hearing children on tests assessing oral receptive language, as well as on a number of EF tests, but no significant differences emerged between the implanted and nonimplanted deaf groups. Language ability was significantly positively associated with EF in both hearing and deaf children. Possible interpretations of these findings are suggested and the theoretical and clinical implications considered.